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arXiv · 1801.06174

Collisionless Magnetic Reconnection in Curved Spacetime and the Effect of Black Hole Rotation

Luca Comisso·Felipe A. Asenjo
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Abstract

Magnetic reconnection in curved spacetime is studied by adopting a general relativistic magnetohydrodynamic model that retains collisionless effects for both electron-ion and pair plasmas. A simple generalization of the standard Sweet-Parker model allows us to obtain the first order effects of the gravitational field of a rotating black hole. It is shown that the black hole rotation acts as to increase the length of azimuthal reconnection layers, per se leading to a decrease of the reconnection rate. However, when coupled to collisionless thermal-inertial effects, the net reconnection rate is enhanced with respect to what would happen in a purely collisional plasma due to a broadening of the reconnection layer. These findings identify an underlying interaction between gravity and collisionless magnetic reconnection in the vicinity of compact objects.

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Luca Comisso, Felipe A. Asenjo. 2018-01-18. Collisionless Magnetic Reconnection in Curved Spacetime and the Effect of Black Hole Rotation. https://doi.org/10.1103/physrevd.97.043007

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